Choose the Main Course

• In a traditional bento box, half of the contents consist of rice. Sometimes the rice is topped with seasoning or a pickled plum, called umeboshi. For a less traditional take on the bento lunch, replace the rice with noodles or another starchy dish. Sandwiches, pasta or bread can replace the rice. If you prefer less carbohydrates, adjust the ratios and make vegetables, eggs or meat the main course.

Pack in Protein

• Half of the remaining food in the bento box is traditionally the protein. Fish is common in a Japanese lunch, but you can replace it with luncheon meats, chicken, beef or pork. Boiled eggs or a tuna, chicken or egg salad also provide a protein-rich alternative. Dairy products, such as cheese or yogurt, can be all or part of the protein part of your bento box, if desired.

Eat Your Veggies

• The final portion of a bento box is the vegetables and fruit. Raw fruits and vegetables require little preparation and they pack well for a cold lunch. Most fruits, snow peas, celery sticks, raw carrots and cucumbers work well when served raw. You can also include a fruit or vegetable salad. Unless you have a way to warm up your lunch, cooked vegetables aren't usually flavorful when eaten cold.

Finishing Touches

• Japanese bento boxes sometimes include pickled vegetables or a small treat, so feel free to round out your lunch with something sweet. Most foods are cut small so you can eat them with chopsticks, but you can skip this step if you send the lunch with western-style utensils. When packing the lunch, it's important to keep cold foods at temperatures below 40 degrees Fahrenheit so they stay safe to consume. If your bento box isn't insulated, pack it in an insulated pouch and add a frozen cold pack. Make sure the foods are thoroughly chilled when you pack them.